


Under The Sea

by Cameo1886



Category: Disney Princesses, Supernatural, The Little Mermaid (1989)
Genre: F/M, M/M, Merman Castiel, Prince Castiel, Prince Dean Winchester, Prince Sam Winchester, Ursula!Crowley
Language: English
Status: In-Progress
Published: 2017-02-03
Updated: 2017-02-03
Packaged: 2018-09-21 19:38:10
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,650
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9563456
Author URL: https://archiveofourown.org/users/Cameo1886/pseuds/Cameo1886
Summary: Castiel, one of the princes of the underwater kingdom Atlantica, has found himself fascinated with a human whose ship had weighed anchor just above his kingdom. As time goes on he finds himself slowly falling in love and wishes he could be with the human prince. With a little bit of encouragement from his brother Castiel finds a way to be with his Prince, though it isn't the most orthodox way. He did sell his soul after all. But it's no big deal. As long as the human falls in love with him in time he can stay with him and get his soul back. Shouldn't be too hard, right?





	

**Author's Note:**

> Hey, guys. This is a first for me, I'm relatively new to this whole big fic thing. I hope you guys like it! I really appreciate feedback, so don't be afraid to say something. Enjoy!

The ocean was calm today. The sky was covered with light grey clouds, making the breeze blowing across the surface colder than it actually was. Once in awhile, a light rain would spatter across the surface but it was always calm. There would be no storms with thrashing waves and screaming winds. It was peaceful. It was the same beneath the waves. The deep blues and greys set the mood almost perfectly. Today was a great day for treasure hunting. 

At least that’s what Gabriel said. Castiel wasn’t sure there was such a thing as a perfect day for treasure hunting. It wasn’t that much different from any other day. He sighed as he followed his older brother past the shoals and out into the deeper waters. Shipwrecks were ahead and that’s what Gabriel was after. Cas glanced forward once in awhile to keep his brother in sight, always looking for the golden colored scales of his tail to make sure he was near. 

The young mermen had snuck away from the confines of their kingdom, though Gabriel practically had to drag Castiel the first half of the way. Eventually, he resigned and came willingly, more or less though he was certain Michael or even Uriel would come looking

“Hurry up, Cassie. I will leave you behind,” Gabe called, diving downwards, following the slope of the ground.

He huffed. “You force me to come and then threaten to leave me behind?”

Gabe smirks. “If you just keep up you don’t have to worry about it.” He doesn’t even look back at his brother as he continues downward. 

He rolled his eyes. With a few powerful flicks of his tail, Castiel was catching up with his brother, who looked over at him with a mischievous grin on his face. “Are you sure you know where you’re going?” He asks, looking forward. All he could see was sand and water. 

With a dramatic sigh, Gabriel twisted slowly in the water as he swam. “Have faith in me, little brother. I’ve been to this wreck before. I didn’t have time to explore at all but I know where it is. Besides, I am a magnet for fun so we couldn’t get lost if we tried.” Cas rolled his eyes. He and Gabriel both had very different ideas of fun.

“You know if dad hears about this-”

“Dad won’t care.” Gabe snaps. “He doesn’t care about what we do.” Castiel sighed and stayed quiet after that. He hadn’t meant to darken the mood, but he certainly had. Their father wasn’t the best when it came to involvement in his kids’ lives. In fact, he was kind of the worst.

After a few minutes, the sandy floor ended in a drop-off, leading to their destination. As they swam over the edge their shipwreck came into view. It wasn’t very old, only a few months Ships went down often in this area and that made for a very fun time. The wrecked hulls were always full of interesting things. Gabriel had a stash of human items at home that he liked to try and show off to their siblings. He came to these places frequently and got tired of coming alone. So Castiel was the one faced with accompanying him. 

He could see why Gabriel liked these so much. There was an air of mystery about them, something that piqued his interest. The darkness unsettled him slightly, but not enough to make him wary. Cas found a smile making its way onto his face. “I told you it was awesome.” He didn’t even have to look over to know Gabe was wearing a smug expression. 

Without waiting he took off towards the pile of wood that was once a proud vessel. He couldn’t help but feel excited and nervous at the same time. The closer he got the more somber he felt. There was a dark feeling about this place, excited as he was. He gently stroked his fingers across the wood, swimming slowly along its side. 

“Come on, Cassie.” Gabe dove downwards, trailing the curved edge of the hull until he came to where the wood rested in the sand. There was a small, jagged opening that was barely big enough for one of them at a time to fit into. Cas looked back at his brother, who grinned back at him. “Ladies first.” 

Castiel moved down through the gap, careful of the broken pieces of wood. The last thing he wanted to do was hurt himself. That would be nothing but trouble. He wiggled his way through, stirring up the sand as he did. He heard his brother huff as he began to swim into the deceased vessel as well. Cas moved aside, looking around. It was dark inside the ship, hard to see. If his eyes weren’t so good, he would’ve been lost in the darkness for sure. 

The sea was beginning to claim it as her own forever now. Green plants had already made their way inside, starting to cover every surface. The floor was covered in sand that had been washed in by the soft currents in the area. The wooden squares were strewn about, those that were still intact at least. The rest that was broken had sunk, becoming waterlogged and finding their final resting place on the floor of the derelict. The room they entered into was full of wooden boxes. It looked as though it had been some sort of storage area. 

“Agh!” There was a short, sharp cry from behind him. Cas turned quickly. Gabriel finished squirming into the opening and as soon as he was free looked down at his tail. About halfway down there was a jagged cut, a few of the golden scales missing, having been torn away by the wood. It wasn’t deep but it was enough to draw blood. He hissed and pressed his hand to it. 

“Are you alright?” Cas asks, concern lacing his voice. 

“Yeah, yeah, I’m fine.” Gabe waves him off. “I can handle a little scratch.” It wasn’t just a little scratch, but whatever. “Let’s go.” He was apparently already tired of this room. He swam along the ceiling, making a noise of triumph when he found the exit. It went upwards, leading further up into the ship. 

The further up they went, the more interesting things got. The top levels were more open. The side opposite of the one they entered on had a gaping hole leading out to the rest of the open water and exposing two of the decks at the same time. Cas looked over at his brother, who was staring at the opening unamused. Cas opened his mouth to comment about the wide-open entryway but he was cut off. “Don’t. Not a word.” He huffs and continues on exploring, mumbling under his breath. 

Castiel decided to take off on his own. With a light flick of his tail, he was moving through the passages, keeping an eye out for anything that might be interesting. This layer of the ship was covered in more ocean life than the bottom part was. Long bits of seaweed and other plants had claimed this place as home. Small colorful fish darted about once in awhile, startled by the newcomer. Bigger fish were a little rarer, but they also appeared on occasion. 

He was about to leave the room when a small glint caught his eye. He dove a little, making his way to the floor to retrieve the item. It was metallic, somewhat silver in color though a green crust had begun to corrode over it. Castiel picked it up with interest.  
It was slim and just longer than his hand, widening a bit towards the end. The wide end part split into three long prongs. It looked like it could have been used to grab things, or maybe even stab them. It was too small to be a weapon, though. He decided to hold onto it to see if Gabriel had any ideas about what it was. 

He resumed his search, uncovering a few other interesting things in the next room. There was a shelf of some sort, lying sideways with four long legs sticking out of the bottom. There was another wooden square of some kind, but this one was longer and flatter. There was also some sort of lock holding the container closed.

With some effort, Castiel managed to pry the rusted clasp open. Lifting the lid was another challenge in and of itself at it made some horrible noises as it moved. Once it was open enough that Castiel could see easily inside of it, he let go. The rusty hinges held it in place. The contents of the wooden case were less exciting than Castiel had hoped they would be but that didn’t mean they weren’t interesting. 

The chest was filled with cloth of different kinds, gently floating now that they’d been released from their confinement. He reached out, pulling one of the pieces of cloth closer. It was a rough material, white and in surprisingly good condition. He couldn’t figure out for the life of him the purpose of it, though. It was oddly shaped and filled with holes. There was one wide piece and coming off of the sides near the top were two long, thin pieces, each piece ending with a hole. What was the point? The chest was full of these mysteries, as well as some other ones he couldn’t even begin to guess at or explain. He gave up trying to figure it out and left the items to their fate. He departed, making sure to grab the metal pronged item before departing.

The next area he visited was a level above the one with the pointless cloth creations. The room was long, spanning nearly the entire length of the ship and it was just wide. This entire level had squares cut into the sides, providing a clear visual of what was outside. For half a moment Castiel thought he saw a large shadow pass over but he quickly wrote it off and turned his attention back to the room. 

A few of the squares had big, long metal things tied to them. They were made of some sort of dark metal, big and bulky on one end with the long tube-like part poking out of the squares in the ship’s side. They seemed like they had lined both sides of the ship at one point but some had broken loose and were piled up on one side while a few others remained in their original places. Castiel moved to examine the ones that were piled up but then he saw something that made him freeze where he was, shivers rattling through his scales. 

A human. Well...what was left of one. Most of the flesh was gone, picked away by the little fish that lived here but the bones were there and very much whole. One of the human’s two tails was pinned between two of the big, iron things. He knew humans couldn’t breathe under the water like he and his kid could. This one must have gotten stuck here and ran out of breath as the ship sank. Castiel couldn’t help but feel sad for the human. Hopefully running out of breath underwater had meant a quick demise for the poor creature. 

He decided it would be for the best to leave the room. He was about to leave to the final level when Gabriel suddenly darted inside, pushing him back into cover.

“Gabe, what-”

“Shark.” He said quickly and quietly. “It’s swimming right outside above the top deck.” 

This was not good. Needless to say, sharks and merpeople did not get along. Large numbers of the deaths in their colonies were attributed to those who weren’t careful enough around sharks. They could outmaneuver a shark easily, but out in the open it was a different story and he highly doubted his little, pronged not-weapon would be defense enough.

Castiel felt nerves making their way to his mind. The shadow he’d seen earlier really wasn’t his imagination. “Let’s just go back the way we came,” he says. “It won’t see us then until we’re far enough away it won’t chase.” 

Gabe nods. “Just be quiet. Don’t mess anything up.” With that, he turns to swim back towards their point of entry. Cas did his best not to make any unnecessary movements as they went. Any big enough vibrations would definitely alert the shark of their presence if it wasn’t already. He found himself not even wanting to breathe as he followed his older brother through the sunken craft. 

As they approached the wide open hole in the side they’d passed earlier Gabe paused. For all they knew it could be right outside. He exhaled slowly but took in a sharp breath as Cas moved to look out. He grabbed his little brother’s fin and pulled him to a stop. 

“What do you think you’re doing?”

“I’m just going to look.” He defended. “I want to know where it is. If we know where it is we can time our escape better.” 

The elder huffed. “Fine. But if you get eaten I’m telling everyone it was your idea to come out here.”  
Castiel rolled his eyes again. “Fine.” With that, Gabriel let go of him. He moved to the edge, slowly peeking around the corner. Nothing. He looked to the left, then to the right. It seemed clear. Before Gabe could stop him he swam out completely, keeping impossibly close to the wood as he swam upwards towards the deck of the ship. 

He heard his brother call his name but ignored him. He was going to find out where this shark was. He reached the deck, pausing before looking over the edge. He eve so slowly peeked over the edge. 

The top of the ship was still mostly intact. The long wooden poles still stood from the middle, though all of the cloth that was usually attached them was gone. He carefully scanned the whole area, sure to look everywhere. The shark wasn’t here either. Had Gabe been imagining things?

Castiel heard Gabriel’s warning too late. He bolted forwards, trying to make it over the edge of the deck as teeth scraped against his scales. The force of the impact sent him reeling hear over tail. He struggled to orientate himself as the stinging in his tail began. He hadn’t been bitten but he’d just barely avoided it. Panic began to set in as he finally righted himself. The shark was circling back.

He dove over the side, moving downwards as fast as he could. Gabriel met him halfway, making sure he was alive. The pair bolted inside the wooden structure as the shark came around for another attack. They didn’t stop until they were back in the room they’d entered from. Both were panting and Castiel could feel his entire body shaking. 

“Cassie, look at me!” He hadn’t even realized that Gabe was talking to him until his brother’s hands were on his shoulder. 

“I’m fine,” He says quickly, brushing his hands away. “I’m fine, it just grazed me.” He looks down at his tail. He was bleeding, jagged lines of missing blue scales were showing very clearly where the shark had nearly had him. He was lucky to even be alive. “We need to get out of here.” 

“Are you good enough to make it home?” 

“I’m fine, Gabe. It’s not that bad.” 

He nods. “Ok. Let’s go. Just be careful, ok?” He sighs. “This would be a great time to actually be good at magic. Definitely practicing later on.” 

“Is this really the time?” Cas looks back at him, eyes narrow. 

“There’s always time for magic, little brother.”

Castiel shakes his head and moves over to their entry point and starts working his way back through. He grits his teeth as sand grinds into his wounds but decides to ignore it. He can worry about it when he gets home. 

Gabriel takes the lead once they’re both out. They stick close to the sand, taking cover in the shadow of the vessel. “Okay…” Gabe says softly. “Where are you?” He mumbles to himself as he starts looking. He’s worried the shark will sense Cas’s blood and find them that way. 

It seems luck is on their side. The predator is nowhere to be seen. The brothers make a break for it, leaving the wreck behind and hurriedly heading towards home. They’re both quiet as they swim. At least until Gabe sees that after all of that Cas is still holding onto the tined object.  
“Are you kidding me?” He asks, coming to a complete stop. Castiel looks back at him, confused. “You almost get eaten and you still manage to hold onto that thing?” He shakes his head. “You are something else.” 

Cas smiles and looks down at the object. Clearly, Gabriel didn’t know what it was. If he did he would have already made some sort of comment about it which would have been followed by more comments about how smart he was. Cas found himself almost glad Gabe didn’t know what it was. He wasn’t sure how much more of his brother’s ridiculous bragging he could take. 

The boys entered the kingdom discreetly, avoiding everyone they could. People were sure to notice the injuries and ask what had happened. There would be no keeping the information from their family now, but there was no sense in alerting the entire population. 

No sooner had they reached home they were cornered. Well, Castiel was cornered. Gabe managed to slip out before Michael could catch him. “Where have you been?” He asked. He clearly wasn’t happy. “Father’s had us looking for you two for over an hour.” 

Castiel was legitimately confused. “I can’t imagine he was that worried.” 

That earned him a glare from his eldest brother. “He thought you and Gabriel had wandered to the surface. Again.” He looked down. He and Gabe had ventured to the surface before, but it had been uneventful. Nothing had happened. “You know that’s against the laws, Castiel.” 

“We weren’t at the surface.” He says. He wouldn’t allow Michael to relay falsehoods to his father. He went to move around his brother, but the elder blocked his path.

“Don’t lie to me. I know you and Gabriel went to the surface to see those ships.”

Ships? He hadn’t heard anything about the ships. 

“We didn’t go to the surface.” He repeats.

Again he tries to leave but can’t. “What is that?” Michael asks, pointing to the tined object in his hand. 

“Nothing.” He says, irritated. With slight movements, he swims up and around his brother. He can feel Michael’s eyes on his tail as he goes but he isn’t about to tell him what happened. Let him try to get the story from Gabriel. That was an altercation Cas would love to see.

By the time he found him, his elder brother was already relaying their story to their other brother, Balthazar. The blonde looked over at him as he approached, grinning. Gabriel looked over and smiled too. Cas couldn’t help but wonder what fairy tale his older brother had fabricated to make him grin like that. 

“Cassie!” Balthazar swam to meet him. “Our dear older brother tells me you’re lucky to be alive. A shark, really?” Without warning, Balthazar swims around him to look at the teeth marks. After examining them, and successfully making him uncomfortable, he moves back around. “You really were telling the truth.”

Gabriel scoffs with mock offense. “I would never lie! Not about somebody almost dying anyways.”

“As long as you don’t tell Michael.” 

The golden scaled merman let out a long, irritated sigh. “Already?”

Cas nods. “He cornered me, wanting to know where we were.”

Balthazar interjects. “Forget Michael, I can’t believe you went without me.” He crosses his arms over his chest. “That hurts, Gabriel, that you would choose our stick in the mud little brother over me. It really hurts.” 

“If it makes you feel any better, I have this.” He holds his treasure up. It is promptly snatched from his hand for examination. “Be careful with it.” He says. 

Again, eyes are rolled and his statement ignored. “Hmmm…” Balthazar turns it over in his hands a few times, thinking hard about what it could be. “Well, Cassie, I believe you’ve got yourself something very special.” 

“Do I?”

“Oh, yes indeed!” He smiles, presenting the object back to him ceremoniously. “You seem to have found some sort of grooming utensil.” 

His expression falls. “What?” He looks it over again. “I don’t think that’s right.” 

“Of course it is. Even if it isn’t, it’s not like you have any better ideas as to what it might be.” Cas would have loved to protest, but Balthazar was right, making keeping his silence seem like the best option. 

“You don’t know what you’re talking about,” Gabriel accused. “You don’t have the foggiest clue.”

“Neither do you, so what’s the difference?” Balthy retorted. “But, if you really want to know you should go see for yourself.” 

“That’s right,” Castiel confirmed. “Michael said there are ships above us. He thought that’s where we went.” 

He watched Gabriel light up. “Ships? What are we still doing here, let’s go!” 

Castiel’s own protests were drowned out by the long dragging groan of his other brother. “Can’t we at least eat lunch first?”  
Gabe paused, considering Balthazar’s proposal. “Alright. Lunch first, then we go see the ships.” 

“Deal.” 

The two of them promptly took off in search of their midday meal.

Another adventure so soon? These two would be the death of him. As much as he wanted to, he couldn’t deny the newfound spark of interest burning within. This was going to be interesting.


End file.
